Cook the lentils in a small saucepan according to the directions on the packet. Drain and set aside.
Cook mirepoix: Meanwhile, heat the olive oil in a large saucepan or Dutch oven over medium-high heat. Cook the onion, carrots, and celery for about 5 minutes, or until the onion is translucent. Stir frequently.
Cook aromatics: Add the garlic, oregano, thyme, and crushed red pepper. Cook for 1 minute, stirring constantly. Add the tomato paste and potato. Cook for 1 minute more, stirring constantly.
Add liquids: Pour in the diced fire roasted tomatoes, vegetable broth, and 2 cups water. Add the bay leaves and bring to a gentle boil.
Add pasta: Reduce the heat to a simmer, stir in the pasta, and cook covered for about 15 minutes, or until the pasta and potato are al dente. Stir occasionally.
Mix ingredients: Add the lentils, white beans, nutritional yeast, and baby spinach. Simmer for about 5 minutes more, or until the spinach is wilted and the soup is warmed through. Add more vegetable broth or water as desired.
Season: Remove the bay leaves. Add the lemon zest and juice. Season with salt, pepper, and more lemon juice to taste. Add maple syrup to taste. Garnish with parsley.